The three research areas include diverse topics outside the traditional chemistry disciplines. For example, biochemistry and biotechnology research includes reactivities of metal ion complexes by high field NMR, intercalation with DNA by UV-visible spectroscopy, free radical biochemistry, and identification of genes in red oak; chemical synthesis includes green chemistry, materials and polymer science; environmental chemistry projects include environmental monitoring, bioremediation, and entomology.
Below is a brief description of current research projects directed by the chemistry faculty.
Cynthia A. Atterholt, Ph.D. - Analytical Chemistry
Controlled Release Pheromones for Insect Pest Management
Dr. Atterholt’s research involves the study of pheromones used for mating disruption as an alternative method to pesticides. There is an increasing interest in alternatives to pesticides to minimize pesticide residues on food, as a health and safety concern of agricultural workers, and to provide a general understanding of environment impact. Safe alternatives to pesticides are needed to insure a food supply that is adequate to feed a growing world population.
David J. Butcher, Ph.D. - Analytical Chemistry
Decline of High Elevation Conifers in the Southern Appalachians
Fraser fir (Abies fraseri), which are native to the Southern Appalachians, have experienced severe decline over the last forty years, primarily due to attack by an exotic insect, the balsam woolly adelgid. We have been studying differences in the chemical composition of the seeds and foliage of these trees to attempt to characterize chemical differences between trees that make individuals or stands more resistant to attack by this pest. The native habitat of these trees are scenic areas such as the Great Smoky Mountains National Park and the Blue Ridge Parkway; this species also is important as a Christmas tree. Because tourism and Christmas tree farms are significant industries in this region, the decline of the Fraser fir is potentially an economic loss to this region.
Phytoremediation at Barber Orchard, NC
Barber Orchard is a 500-acre residential housing development located approximately five miles west of Waynesville, NC and 20 miles from the WCU campus. It is currently listed as a Superfund site by the U.S. EPA because of high soil concentration levels of arsenic, lead, and organo-pesticides. The contamination was caused by pesticide use when the land was used as an apple orchard throughout most of the twentieth century. The EPA is currently conducting a remedial investigation/feasibility study to consider future action to be taken at Barber Orchard.
Aster Dewanti, Ph.D. - Biochemistry
Enzymology of quinoprotein glucose dehydrogenases
Quinoproteins are a relatively new class of enzymes catalyzing oxidation/reduction reactions. They use quinone cofactors to help catalyze the electron transfer reactions. Some of these cofactors are covalently bound and others are not, like the ones in glucose dehydrogenases. The glucose dehydrogenases catalyze the oxidation of glucose to gluconolactone, which is spontaneously hydrated to gluconic acid in aqueous solution. There two known glucose dehydrogenases in Acinetobacter calcoaceticus, the soluble one is well studied and has a turnover number of 6000/sec, but as yet an unknown function, and the membrane-bound one functions when the organism is under stress (turnover number ~ 600/sec). The soluble glucose dehydrogenase is a dimer made up of two monomers and shows a negative cooperative behavior, which is still not understood. This will be something that I will do in the near future—to study what causes the negative cooperativity using a fast-flow technique. Quinoprotein glucose dehydrogenase is used in a dipstick (Roche) to measure blood sugar in diabetic patients.
Brian Dinkelmeyer, Ph.D. - Organic Chemistry
Green Chemistry
Dr. Dinkelmeyer’s research interests involve the development of environmentally benign chemical processes. Organic solvents are a major source of pollution from the chemical industry. Processes that reduce or eliminate the use of organic solvents would be a major improvement over current technologies. The focus of this current work is in the development of solvent-free methods for synthesizing high-molecular weight polymers. Polybutadiene polymers will be the focus of our research efforts as these polymers are of significant industrial interest.
Carmen Huffman, Ph.D. - Physical Chemistry
Shedding Light on Photosynthesis: How Environmental Conditions Influence Photosynthetic Pigment Function
My research focuses on the structure/function relationship of light-harvesting pigments found in the thylakoid membranes of higher plants that undergo photosynthesis. Structure is resolved using surface tension measurements and attenuated total reflection Fourier transform infrared spectroscopy. The structure of the pigment/membrane complex is observed as a function of various environmental conditions such as pH, ionic strength, and membrane composition. Then, the structure/function relationship can be determined by monitoring the efficiency of an artificial photosynthesis process with various structures as dictated by the environmental conditions.
Emily Jellen-McCullough - Analytical Biochemistry
Biological Mass Spectrometry
Mass spectrometry is a powerful tool that can be used for solving problems in many areas of chemistry. We are interested in determination of protein sequence and structure of various biologically relevant proteins. There are extensive protein and DNA databases available. Using these databases, theoretical fragments of protein cleavage can be created and them compared to the experimental masses of known peptide fragments.
Alternate projects include determination of relative bond strength of various non-covalent compounds of biological interest. Understanding the structure, dynamics, and strength of these interactions can give great insight to the nature of binding, structural configuration, and function of a non-covalent complex. If thermochemical information, such as binding energy and reactivity, is known about a system, it may facilitate investigations of protein structure and function, which are not well understood. In addition to experimental approaches, semi-empirical and ab initio calculations of geometry and binding energies can be utilized in the supplementation and validation of the results.
William R. Kwochka, PhD - Organic Chemistry
Carbon and Oxygenated Cyclophanes
We have investigated the formation of all-carbon cyclophanes. We were successful in preparing a variety of these large ring systems using the Suzuki-Miyaura coupling of aryl dibromides with bis-9-BBN adduct of dienes. The yields of these couplings were predictably low since we are forming as many as four bonds sequentially in one reaction vessel and there is no mode of pre-organization. Single crystal x-ray analyses of the [n.n]cyclophanes reveal interestingly shaped molecules with large cavities.
Jack Summers, PhD - Inorganic and Bioinorganic Chemistry
Reactivities of Metal Ion Complexes by Phosphorus Relaxation Enhancement
Research in Dr. Summers' laboratory focuses on elucidating the factors that determine the reactivities of metal ion complexes, with specific emphasis on chemistries of biological or clinical importance. The work relies heavily on novel NMR methods called Phosphorus Relaxation Enhancement (PhoRE). PhoRE methods were developed by Dr. Summers and colleagues to characterize reactivities of paramagnetic metal ion complexes. The work can be classified into three areas, (1) initial work to develop the methods, (2) studies on nucleic acids, and (3) studies on proteins and peptides.